Combination of Dehumidifier, Heat Pump and Air Heater: Influence of Temperature, Specific Humidity, And Mass Flow Rate of Air on Specific Energy Consumption

Global warming, climate change, and ever-increasing energy demand are among the pressing challenges currently facing humanity. Particularly, indoor air conditioning, a major source of energy consumption, requires immediate improvement to prevent energy crises. In this study, various airfoil profiles were applied to create a window-type convection device that entrains air to improve convection between indoor and outdoor airflows and adjust the indoor temperature. How the geometric structure of the convection device affects its air entrainment performance was investigated on the basis of various airfoil profiles and outlet slit sizes of the airflow multiplier. The airfoil profiles were designed according to the 4-digit series developed by the National Advisory Committee for Aeronautics. The results revealed that airfoil thickness, airfoil camber, and air outlet slit size affected the mass flow rate of the convection device. Overall, the mass flow rate at the outlet of the convection device was more than 10 times greater than at the inlet, demonstrating the potential of the device to improve air convection. To validate these simulated results, the wind-deflector plate was processed using the NACA4424 airfoil with a 1.2 mm slit, and various operating voltages were applied to the convection device to measure the resulting wind speeds and calculate the corresponding mass flow rates. The experimental and simulated results were similar, with a mean error of <7%, indicating that the airfoil-shaped wind-deflector plate substantially improved air entrainment of the convection device to the goal of reduced energy consumption and carbon emissions.

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Experimental Investigation on Flow Characteristic of Stepped Capillary Tube for Heat Pump Type Air Conditioner with R410A

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.960-961.643 ◽

2014 ◽

Vol 960-961 ◽

pp. 643-647

Author(s):

Yan Sheng Xu

Keyword(s):

Mass Flow Rate ◽

Heat Pump ◽

Mass Flow ◽

Flow Rate ◽

Capillary Tube ◽

Coefficient Of Performance ◽

Tube Length ◽

Air Conditioner ◽

Capillary Tubes ◽

Tube Assembly

A stepped capillary tube consisting of two serially connected capillary tubes with different diameters is invented to replace the conventional expansion device. The mass flow rate of refrigerant R410A in stepped capillary tubes with different size were tested. The model of stepped capillary tube is proposed, and its numerical algorithm for tube length and mass flow rate is developed. The experimental results show that the performance comparing between stepped capillary tube system and capillary tube assembly system, the cooling capacity is reduced by 0.3%, the energy efficiency ratio (EER) is equal to each other, the heating capacity is increased by 0.3%, the coefficient of performance (COP) is decreased by 0.3%. That is to say, the performance index of the two kinds of throttle mechanism is almost identical. It indicates that the stepped capillary tube can replace the capillary tube assembly in the R410A heat pump type air conditioner absolutely. The model is validated with experimental data, and the results show that the model can be used for sizing and rating stepped capillary tube.

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Thermal Performance Analysis and Optimization of Solar Assisted Heat Pump Water Heater

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.592-594.2416 ◽

2014 ◽

Vol 592-594 ◽

pp. 2416-2421

Author(s):

R.N. Kokila ◽

S. Rajakumar

Keyword(s):

Mass Flow Rate ◽

Heat Pump ◽

Mass Flow ◽

Flow Rate ◽

Thermal Performance ◽

Optimization Technique ◽

Direct Expansion ◽

Water Heater ◽

Rate Optimization ◽

Flat Plate Collector

The main objective of this paper is to analyze the thermal performance of direct expansion solar assisted heat pump DX-SAHP(A) by numerical simulation in MATLAB and comparing it with the thermal performance of DX-SAHP(B) which has an optimized collector area and mass flow rate. Optimization is performed for high exergy efficiency using Particle Swarm Optimization (PSO) and Artificial Bee Colony (ABC) optimization technique. The flat plate collector of solar water heater is used as the evaporator with refrigerant (R22).With the optimized value of mass flow rate as 0.055 kg/sec, width as 0.03 m and diameter of riser tubes as 0.021 m the performance of the optimized system has a maximum COP of 6.85 which is greater than the COP of DX-SAHP(A) and the final water temperature of is obtained 100 minutes earlier in the optimized system i.e. DX-SAHP(B) with compressor work less than the system A

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Modeling of Bifacial Photovoltaic-Thermal (PVT) Air Heater with Jet Plate

International Journal of Heat and Technology ◽

10.18280/ijht.390409 ◽

2021 ◽

Vol 39 (4) ◽

pp. 1117-1122

Author(s):

Win Eng Ewe ◽

Ahmad Fudholi ◽

Kamaruzzaman Sopian ◽

Nilofar Asim

Keyword(s):

Mass Flow Rate ◽

Air Temperature ◽

Mass Flow ◽

Flow Rate ◽

Thermal Efficiency ◽

Solar Irradiation ◽

Electrical Efficiency ◽

Air Heater ◽

Packing Factor ◽

Pv Panel

This research demonstrates how to develop a novel energy balance equation to investigate heat transmission between the components of a bifacial photovoltaic-thermal (PVT) air heater with a jet plate. The temperature output and efficiency of the system are shown. A greater mass flow rate reduces the exit air temperature and increases the thermal efficiency of the thermal component. Increased sun irradiation raises the output air temperature and thermal efficiency. In terms of electrical efficiency, a greater mass flow rate reduces the temperature of the PV panel while increasing electrical efficiency. On the other hand, higher solar irradiation raises the temperature of the PV panel, lowering its electrical efficiency. The maximum thermal efficiency of BPVTJPR is 51.09% under the circumstances of 12 PV cells with a packing factor of 0.66, a jet plate reflector with 36 holes, 900 W/m2 solar irradiances, and a mass flow rate of 0.035 kg/s. The maximum electrical efficiency of BPVTJPR is 10.73% under the circumstances of 12 PV cells with a packing factor of 0.66, a jet plate reflector with 36 holes, 700 W/m2 solar irradiances, and a mass flow rate of 0.035 kg/s.

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Thermal and Cost Analysis of a Multi-Pass Solar Air Heater with Reversed Absorber and Reflector

International Journal for Research in Engineering Application & Management ◽

10.35291/2454-9150.2020.0379 ◽

2020 ◽

pp. 141-146

Keyword(s):

Cost Analysis ◽

Mass Flow Rate ◽

Mass Flow ◽

Flow Rate ◽

Cost Effective ◽

Solar Air Heater ◽

Constant Mass ◽

Air Heater ◽

Effectiveness Model ◽

Solar Intensity

Solar air heater is a major component of solar dryer. A model of multi pass solar air heater (MPSAH) with reversed absorber and reflector was developed. Exhaustive Study over the performance of MPSAH with and without reversed absorber and cost analysis was done. The performance curves show the effect of solar intensity on MPSAH with and without reversed absorber at constant mass flow. It was observed that the thermal efficiency of MPSAH is depending on solar intensity and losses when mass flow rate remain constant. At constant mass flow rate 26.90 gm/sec, the collector efficiency increased by 9% at average solar intensity 457w/m². Theoretical and experimental analysis showed close agreement. In addition the cost-effectiveness model has been used to examine the performance MPSAH with and without reverse absorbers. The air heaters annual cost (AC) estimation and annual power acquirement (AG) was analyze. The result is evidence for that multi-pass solar air heater with reverse absorbers and reflector is more cost-effective than multi-pass solar collectors without reverse absorber.

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Implementation of a Floating Head Pressure Condensation Control to Reduce Electrical Energy Consumption in an Industrial Refrigeration System

Applied Sciences ◽

10.3390/app112411923 ◽

2021 ◽

Vol 11 (24) ◽

pp. 11923

Author(s):

Fábio Luiz da Costa Carrir ◽

Cesare Biserni ◽

Danilo Barreto Aguiar ◽

Elizaldo Domingues dos Santos ◽

Ivoni Carlos Acunha Júnior

Keyword(s):

Energy Consumption ◽

Mass Flow Rate ◽

Mass Flow ◽

Flow Rate ◽

Electric Energy ◽

Electrical Energy ◽

Industrial Facilities ◽

Improve Energy Efficiency ◽

Electric Energy Consumption ◽

Industrial Refrigeration

The growing global demand for energy and the costly taxes on electric energy demonstrate the importance of seeking new techniques to improve energy efficiency in industrial facilities. Refrigeration units demand a large amount of electricity due to the high power needs of the components of the system. One strategy to reduce the electric energy consumption in these facilities is pressure condensation control. The objective here was to develop a logical control model where the physical quantities in the thermodynamic process can be monitored and used to determine the optimum point of the condensation pressure and the mass flow rate of the air in the evaporative condenser. The algorithm developed was validated through experiments and was posteriorly implemented in an ammonia industrial system of refrigeration over a period of sixteen months (480 days). The results showed that the operation of the evaporative condenser with a controlled air mass flow rate by logical modeling achieved a reduction of 7.5% in the consumption of electric energy, leading to a significant reduction in the operational cost of the refrigeration plant.

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Modeling and PSO optimization of Humidifier-Dehumidifier desalination

International Journal of Renewable Energy Development ◽

10.14710/ijred.7.1.59-64 ◽

2018 ◽

Vol 7 (1) ◽

pp. 59 ◽

Cited By ~ 4

Author(s):

Mohammad Hossein Ahmadi ◽

Mohammad Ali Afshar ◽

Ali Naseri ◽

Mokhtar Bidi ◽

H. Hadiyanto

Keyword(s):

Mass Flow Rate ◽

Mass Flow ◽

Flow Rate ◽

Temperature Difference ◽

Cooling Water ◽

Decision Variable ◽

Solar Air Heater ◽

Air Heater ◽

Output Ratio ◽

Optimum Productivity

The aim of this study is modeling a solar-air heater humidification-dehumidification unit with applying particle swarm optimization to find out the maximum gained output ratio with respect to the mass flow rate of water and air entering humidifier, mass flow rate of cooling water entering dehumidifier, width and length of solar air heater and terminal temperature difference (TTD) of dehumidifier representing temperature difference of inlet cooling water and saturated air to dehumidifier as its decision variable. A sensitivity analysis, furthermore, is performed to distinguish the effect of operating parameters including mass flow rate and streams’ temperature. The results showed that the optimum productivity decreases by decreasing the ratio of mass flow rate of water entering humidifier to air ones.Article History: Received: July 12th 2017; Revised: December 15th 2017; Accepted: 2nd February 2018; Available onlineHow to Cite This Article: Afshar, M.A., Naseri, A., Bidi, M., Ahmadi, M.H. and Hadiyanto, H. (2018) Modeling and PSO Optimization of Humidifier-Dehumidifier Desalination. International Journal of Renewable Energy Development, 7(1),59-64.https://doi.org/10.14710/ijred.7.1.59-64

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